The present invention relates generally to a new and improved method of manufacture of a synthetic stone rail, apparatus for performing the method, and a balustrade product. More specifically, the present invention provides a by manufactured synthetic stone rail article in the form of a balustrade product containing holes for receiving a connecting structure.
In the past, it has been the practice to produce synthetic stone rails with connection holes at opposite ends by using a final drilling step. This method involved a rotatable centrifugal mold having first and second open halves and a cylindrical inner surface adapted to receive a slurry of synthetic stone material, pouring into said first open half of said rotatable mold a predetermined amount of the slurry of synthetic material composition, tightening the mold in a closed state, rotating on a generally horizontal axis the elongated tubular mold causing said substance to acquire the form of a cylindrical lining within said mold in response to the rotation of the mold and resultant centrifugal force. The predetermined amount of fluid material thereby becomes distributed in said cavity in the form of a rail or balustrade product. After opening the first and second halves of the mold and removing the balustrade product, the final step was to produce with a drill a plurality of holes in the balustrade product which are parallel to the balustrade product""s center horizontal axis. However, producing a hole in the balustrade product quickly, in a cost-effective manner, and with proper alignment can be difficult and problematic.
As will be described in greater detail hereinafter, the method and apparatus of the present invention solves the aforementioned problems and employs a number of novel features and devices that render it highly advantageous over the prior art.
Accordingly, it is an object of this invention to provide an improved method and apparatus for forming a balustrade product. It is another object to provide a balustrade having a connection structure that allows for a quick and easy connection of a balustrade with a post or support structure.
As described later in more detail, the problem of producing a hole in the balustrade product quickly, in a cost-effective manner with proper alignment has been solved by my present invention. Further, the previous methods involving drilling in an end of the balustrade product have been obviated.
My present invention fulfills the need for a method and apparatus that produces the hole in the balustrade product quickly, using less steps and equipment, and giving a final product with a properly aligned hole. Specifically, my present invention reduces the time needed to manufacture by producing the necessary hole in the balustrade product during the molding process. More specifically, an insert member inside the mold is used. The insert member is properly aligned within the mold by a plurality of supports. The plurality of supports engage the inside cavity of the mold resulting in properly alignment of a plurality of pipes that engage the plurality of supports. Each pipe is positioned parallel with the mold""s center horizontal axis and produce the necessary hole in the balustrade product. The inside cavity of the pipe is sealed off from the slurry composition and leaves a cavity in the balustrade product after solidification. The plurality of holes are through holes that can be used for various functions including receiving fastener means to attach the rail to another member or fixed support.
Another problem with the known method is that additional equipment and steps were added to the method of manufacturing the balustrade product. First, the balustrade product was molded from a slurry composition by rotational molding. Next, the balustrade product was removed from the mold after solidification. The balustrade product would be then fixed in place while drilling equipment was used to produce the necessary hole in the ends of the balustrade product.
My present invention eliminates this drilling step completely. In addition, I found that the holes that resulted from my present invention had proper alignment with the balustrade product""s center horizontal axis. This solves a problem that existed with the known method. The known method of drilling the holes resulted in a larger number of improperly aligned holes. My present invention has reduced the number of improperly aligned holes. This is an important feature because if a balustrade product had improperly aligned holes, the entire balustrade product was rendered unusable.
In a preferred embodiment, the insert member used to position a plurality of pipes is made of a material that can easily become an integral part of the balustrade product. In addition, the plurality of pipes are made of a material that can become an integral part of the balustrade product, such as a PVC material that is low in cost. The supports are made of a material that becomes integral with the balustrade product including the same material as the slurry material and an inexpensive polymer material.
My present invention fulfills the need for an aesthetically quality balustrade product. I have designed a plurality of tabs located on each support in such a manner to not be visible upon solidification of the slurry product. Specifically the plurality of tabs are shaped and configured to become an integral part of the balustrade product in such a manner as to not be visible on an outside surface of the balustrade product after removal from the mold.
According to my present invention, I have provided a new and improved method for producing by centrifugal molding a synthetic stone rail article of manufacture in the form a balustrade product containing holes, including the steps of: providing a rotatable centrifugal mold having first and second open halves and a cylindrical inner surface adapted to receive a slurry of synthetic stone material, an apparatus in the form of an insert member, each insert member having a plurality of supports and a plurality of pipes, each support having a plurality of tabs, the plurality of tabs are shaped and configured to position each support inside the mold, each tab engages the mold at an inside surface, each pipe passes through the plurality of supports at a plurality of holes in each support, each pipe has an outside surface, each hole has an inside surface, the outside surface engages the inside surface, the plurality of supports positioning each pipe inside the mold, the apparatus in the form of an insert member being set into the mold, which is in an open state, so that the plurality of supports are arranged perpendicular to the mold""s center horizontal axis and the plurality of pipes are parallel with the mold""s center horizontal axis, pouring into said first open half of said rotatable mold a predetermined amount of the slurry of synthetic material composition, tightening the mold in a closed state and thereby pressing the insert member against inner surfaces of the mold and also thereby positioning the pipes, rotating on a generally horizontal axis, the elongated tubular mold causing said substance to acquire the form of a cylindrical lining within said mold in response to the rotation of the mold and resultant centrifugal force, the predetermined amount of fluid material becomes distributed in said cavity in the form of a rail with the insert member integral with the balustrade product, solidifying said fluid material in said rotating mold such as to form a blank hollow cylinder within the balustrade product, and opening the first half and the second half of the mold and removing the balustrade product.
The method for manufacture of a balustrade of synthetic material composition in a preferred embodiment further includes the mold being made from an extruded aluminum. The method for manufacture of a balustrade of synthetic material composition further includes the plurality of supports being made from the slurry material and the plurality of pipes being made from PVC material.
Other objects, features and advantages of the invention will become more readily apparent upon reference to the following description when taken in conjunction with the accompanying drawings, which drawings illustrate several embodiments of the invention.